King mattress in a 13×13 ft master
The short version
Tape a King (76×80 in) in this 13×13 ft master: about 40" on each side and 76" at the foot. clears the 24" walk-space rule. Frames add extra width.
Mattress Tip
Side sleepers need softer foam to relieve shoulder pressure points.
Recommended Bed
King
Dimensions
76"x80"
Best Firmness
Medium
Walking Space
Perfect. You have ample space for nightstands and walking around the bed.
Future-Proofing
Even if you sleep solo, a Full or Queen offers much better resale value and versatility.
Numbers worth knowing
76×80 in
King mattress
Source: US bedding
40"
Side clearance each way
Source: 24" walk-space rule
76"
Foot clearance
Source: 24" walk-space rule
Frequently Asked Questions
- Does a King fit a 13×13 ft master?
- Yes, with ~40" side clearance and 76" at the foot versus a 24" walk-space floor. Nightstands eat more.
- How much walk space should a mattress leave?
- Plan at least 24 inches on any side you walk past so you can make the bed and open a nightstand drawer.
- Do frames change this math?
- Yes. Headboards, box springs, and platform rails add width. Tape the frame outline, not just the mattress spec.
References
- SMPTE(accessed 2026-09-29)
- THX Home Cinema(accessed 2026-09-29)
- OSHA Computer Workstations(accessed 2026-09-29)
- Save-Check Methodology(accessed 2026-09-29)
Other published size checks
Twin mattress in a 10×12 ft guest room
A Twin (38×75 in) in a 10×12 ft guest room leaves ~41" per side and 69" at the foot. clears the 24" walk-space rule. Educational only — measure the space b
Twin XL mattress in a 10×11 ft dorm
A Twin XL (38×80 in) in a 10×11 ft dorm leaves ~41" per side and 52" at the foot. clears the 24" walk-space rule. Educational only — measure the space befo
Full mattress in a 11×12 ft kids room
A Full (54×75 in) in a 11×12 ft kids room leaves ~39" per side and 69" at the foot. clears the 24" walk-space rule. Educational only — measure the space be
Queen mattress in a 12×12 ft master
A Queen (60×80 in) in a 12×12 ft master leaves ~42" per side and 64" at the foot. clears the 24" walk-space rule. Educational only — measure the space befo
Queen mattress in a 12×13 ft couple bedroom
A Queen (60×80 in) in a 12×13 ft couple bedroom leaves ~42" per side and 76" at the foot. clears the 24" walk-space rule.
California King mattress in a 12×14 ft primary
A California King (72×84 in) in a 12×14 ft primary leaves ~36" per side and 84" at the foot. clears the 24" walk-space rule.